assume cs:code
 
code segment
        mov ax,4c00h
        int 21h
start:  mov ax,0
    s:  nop
        nop

        mov di,offset s
        mov si,offset s2
        mov ax,cs:[si]
        mov cs:[di],ax

   s0:  jmp short s

   s1:  mov ax,0
        int 21h
        mov ax,0

   s2:  jmp short s1
        nop

code ends

end start


